Gas Giant Spacecraft All Gassed Up

Launching from Earth in 2011, the Juno spacecraft will arrive at Jupiter in 2016 to study the giant planet from an elliptical, polar orbit. Juno will repeatedly dive between the planet and its intense belts of charged particle radiation, coming only 5,000 kilometers (about 3,000 miles) from the cloud tops at closest approach.

Juno's primary goal is to improve our understanding of Jupiter's formation and evolution. The spacecraft will spend a year investigating the planet's origins, interior structure, deep atmosphere and magnetosphere. Juno's study of Jupiter will help us to understand the history of our own solar system and provide new insight into how planetary systems form and develop in our galaxy and beyond.

Juno's principal investigator is Scott Bolton of Southwest Research Institute in San Antonio, Texas. NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the mission. Lockheed Martin Space Systems of Denver, Colo., is building the spacecraft. The Italian Space Agency, Rome, is contributing an infrared spectrometer instrument and a portion of the radio science experiment.

NASA/JPL

Juno Mission Status Update

The Juno spacecraft completed hydrazine fuel loading, oxidizer loading and final tank pressurizations this week, and now the complete propulsion system is ready for the trip to Jupiter. The spacecraft is currently at the Astrotech processing facility in Titusville, Fla.

Hydrazine is the fuel of choice for most spacecraft because of its stored energy. When the fuel is mixed with the oxidizer, the liquid ignites in the propulsion system's main engine to perform the spacecraft's four large maneuvers. One of these maneuvers includes inserting the spacecraft into orbit around Jupiter in 2016.

With the fueling completion, the spacecraft is 99 percent ready for launch. Once the final thermal blanket closeouts and wet spin tests are complete, the spacecraft will be 100 percent ready for installation onto the Atlas 551 launch vehicle.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. Launch management for the mission is the responsibility of NASA's Launch Services Program at the Kennedy Space Center in Florida. JPL is a division of the California Institute of Technology in Pasadena.